Logical read: Page requested and found in the buffer pool.
Physical read: Page requested, not found, IO exercised to bring it in.
Asynchronous reads: Done by IO servers for prefetching. Typically
identify reads done ahead of time in anticipation that the page will be
needed for the next requests.
The buffer pool hit ratio and these are defined in your Syst. Perf.
Monitor Guide.
HRH, Pierre.
Quote:
> Hi,
> Could any one of you show me some pointers (DB2 manual etc.) where
> I could find description of the output produced by the 'snapshot'.
> For example what is ...
> Buffer pool data logical reads
> Buffer pool data physical reads
> Asynchronous pool data page reads
> etc.
> Also I do I translate all these into 'buffer hit ratio'
> or 'buffer miss ratio' etc.
> Thanks,
> Paul.